try this one, http://www.rapidunlockers.com/
I have unlocked my phone there. very fast service (about 6 hours total ) and cheap, now i can update to any version without having to worry that my phone will be locked ever again.
Only 9.99 for phone unlocks!

I actually need this crap to work on my wife's phone since she works for T-Mobile and they won't allow her to have her phone on the sales floor cause it says Verizon on it, but it's not working!!! ... anyway, she has an iPhone 4S, v5.1.1 - does anyone know if this only works on v6.x?? she refuses to upgrade to v6.x

This only works for Verizon on the iPhone 5 due to the 5 using a sim card to reach the network (LTE). 3G only phones on a CDMA network (Verizon and Sprint) won't work for this due to the fact that the word "Verizon" is text not an image.